The importance of measuring bell housing runout.

Every since I had to replace a head gasket on my 340 back in 1971 (blew the bypass hose when racing at OCIR) and they had to mill the heads, I learned that machining an engine leads to other issues. In this case, the intake manifold bolts didn't align with the head and it was a PITA to get the bolts installed. FSM say to mill the intake when the heads are milled. And they are right!
So, if you have a block align honed, that moves the crankshaft up in the block by the distance honed off the crank bore. This will change your alignment with the trans, thus the need to align the bell housing.
I also hate boring an engine any more than absolutely necessary. My 340 builds are at most +0.020" if at all possible. Why go +0.030" if it isn't needed. I would go +0.010" if pistons were available. Thicker bores are happier bores and will make more power too.
So, I fully support measuring everything.